Which one of the following is least likely to cause a warm autoimmune haemolytic anaemia?
Correct Answer A: Mycoplasma infection causes a cold autoimmune haemolytic anaemia. Systemic lupus erythematous can rarely be associated with a mixed-type autoimmune haemolytic anaemia.
Autoimmune haemolytic anaemia:
Autoimmune haemolytic anaemia (AIHA) may be divided in to 'warm' and 'cold' types, according to at what temperature the antibodies best cause haemolysis. It is most commonly idiopathic but may be secondary to a lymphoproliferative disorder, infection or drugs. AIHA is characterised by a positive direct antiglobulin test (Coombs' test).
Warm AIHA: In warm AIHA the antibody (usually IgG) causes haemolysis best at body temperature and haemolysis tends to occur in extravascular sites, for example the spleen. Management options include steroids, immunosuppression and splenectomy.
Causes of warm AIHA:
Cold AIHA: The antibody in cold AIHA is usually IgM and causes haemolysis best at 4 deg C. Haemolysis is mediated by complement and is more commonly intravascular. Features may include symptoms of Raynaud's and acrocynaosis. Patients respond less well to steroids.
Causes of cold AIHA:
*Systemic lupus erythematosus can rarely be associated with a mixed-type autoimmune haemolytic anaemia
A 33-year-old male patient with a history of recurrent nose bleeds, iron-deficiency anaemia and dyspnoea is found to have a pulmonary AV malformation on pulmonary angiography.
What is the likely underlying diagnosis?
Correct Answer B: Hereditary haemorrhagic telangiectasia (HHT):
Also known as Osler-Weber-Rendu syndrome, hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant condition characterised by (as the name suggests) multiple telangiectasia over the skin and mucous membranes. Twenty percent of cases occur spontaneously without prior family history.
There are 4 main diagnostic criteria. If the patient has 2 then they are said to have a possible diagnosis of HHT. If they meet 3 or more of the criteria they are said to have a definite diagnosis of HHT:
A blood film is reported as follows:
What is the most likely underlying cause?
Correct Answer E:
Blood films: typical pictures:
Hyposplenism e.g. post-splenectomy:
Iron-deficiency anaemia:
Myelofibrosis:
Intravascular haemolysis:
Megaloblastic anaemia:
A 22-year-old man with sickle cell anaemia presents with pallor, lethargy and a headache. Blood results are as follows:
Infection with a parvovirus is suspected.
What is the likely diagnosis?
Correct Answer E: The sudden fall in haemoglobin without an appropriate reticulocytosis (3% is just above the normal range) is typical of an aplastic crisis, usually secondary to parvovirus infection.
Sickle-cell crises:
Sickle cell anaemia is characterised by periods of good health with intervening crises Four main types of crises are recognised:
Thrombotic crises:
Sequestration crises:
Aplastic crises:
Haemolytic crises:
Which one of the following factors is most associated with an increased risk of developing bladder cancer?
Correct Answer C: The following factors are associated with the development of bladder cancer
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